Mask chuck and mask manufacturing apparatus including same

ABSTRACT

A mask chuck may include a base plate including a central region and an edge region surrounding the central region, a head part including a first surface connected to the edge region of the base plate and configured to move on the edge region to be close to the central region or away from the central region, and a pad part disposed on a second surface of the head part opposite to the first surface of the head part. The edge region may include a first edge region extending in a first direction, a second edge region extending in the first direction and spaced apart from the first edge region in a second direction crossing the first direction, a third edge region extending in the second direction, and a fourth edge region extending in the second direction and spaced apart from the third edge region in the first direction.

This application claims priority to Korean Patent Application No.10-2020-0091547, filed on Jul. 23, 2020, and all the benefits accruingtherefrom under 35 U.S.C. § 119, the content of which in its entirety isherein incorporated by reference.

BACKGROUND 1. Field

Embodiments of the invention herein relate to a mask chuck and a maskmanufacturing apparatus including the same, and more particularly, to amask chuck configured to stretch a mask in which deposition holes aredefined therein and dispose the mask on a mask frame, and to a maskmanufacturing apparatus.

2. Description of the Related Art

Display panels include a plurality of pixels. The plurality of pixelseach includes a driving element such as a transistor and a displayelement such as an organic light-emitting diode. The display element maybe formed on a substrate by laminating electrodes and light-emittingpatterns on the substrate. The light-emitting patterns are patternedusing a mask in which holes are defined therein so as to be defined in apredetermined region. The light-emitting patterns may be provided in aregion exposed by an opening.

Recently, in order to enhance the production yield of the displaypanels, equipment and methods for manufacturing large-area masks arebeing developed.

SUMMARY

An embodiment of the invention provides a mask chuck including a baseplate including a central region and an edge region surrounding thecentral region, a head part including a first surface connected to theedge region of the base plate and configured to move on the edge regionso as to be close to the central region or away from the central region,and a pad part disposed on a second surface of the head part which isopposite to the first surface of the head part. The edge region includesa first edge region extending in a first direction, a second edge regionextending in the first direction and spaced apart from the first edgeregion in a second direction crossing the first direction, a third edgeregion extending in the second direction, and a fourth edge regionextending in the second direction and spaced apart from the third edgeregion in the first direction. The head part includes a first head partdisposed in the first edge region and extending in the first direction,a second head part disposed in the second edge region and extending inthe first direction, a third head part disposed in the third edge regionand extending in the second direction, and a fourth head part disposedin the fourth edge region and extending in the second direction.

In an embodiment of the invention, a mask manufacturing apparatusincludes a stage on which a mask frame in which a cell opening definedis disposed, a mask chuck disposed on the stage and configured todispose a cell mask on a first surface of the mask frame adjacent to thecell opening, and an intense-light emitting apparatus configured toirradiate an intense light on a portion between the mask frame and thecell mask. The mask chuck includes a base plate including a centralregion and an edge region surrounding the central region, a head partconnected to the edge region of the base plate and configured to move onthe edge region so as to be close to the central region or away from thecentral region, and a pad part disposed on a first surface of the headpart. The edge region includes a first edge region extending in a firstdirection, a second edge region extending in the first direction andspaced apart from the first edge region in a second direction crossingthe first direction, a third edge region extending in the seconddirection, and a fourth edge region extending in the second directionand spaced apart from the third edge region in the first direction. Thehead part includes a first head part disposed in the first edge regionand extending in the first direction, a second head part disposed in thesecond edge region and extending in the first direction, a third headpart disposed in the third edge region and extending in the seconddirection, and a fourth head part disposed in the fourth edge region andextending in the second direction.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments of theinvention and, together with the description, serve to explainprinciples of the invention. In the drawings:

FIG. 1 is a view illustrating an embodiment of a mask assembly;

FIG. 2 is a perspective view illustrating an embodiment of a mask chuckaccording to the invention;

FIG. 3 is a perspective view vertically inverting and illustrating amask chuck illustrated in FIG. 2;

FIG. 4 is a perspective view illustrating an embodiment of a pad partdisposed on a lower surface of a fourth head part among the pad partsillustrated in FIG. 3;

FIG. 5A is a view illustrating a state before the cell mask illustratedin FIG. 1 is stretched;

FIG. 5B is a view illustrating a state in which the mask chuckillustrated in FIG. 2 picks the cell mask illustrated in FIG. 5A;

FIG. 6A is a view illustrating a state in which the mask chuckillustrated in FIG. 5B stretches a cell mask;

FIG. 6B is a view illustrating a state in which the cell maskillustrated in FIG. 5A is stretched;

FIG. 7 is a view illustrating a state in which the mask chuckillustrated in FIG. 6A disposes a cell mask on a mask frame;

FIG. 8 is a view exemplarily illustrating a state in which the cell maskillustrated in FIG. 7 is fixed to a mask frame;

FIG. 9 is a view illustrating an embodiment of a pad part of a maskchuck according to the invention;

FIGS. 10A and 10B are views illustrating an embodiment of a pad part ofa mask chuck according to the invention;

FIGS. 11A and 11B are views illustrating a state in which a mask chuckincluding a pad part and a head part which are illustrated in FIGS. 10Aand 10B stretches a cell mask;

FIGS. 12A and 12B are views illustrating an embodiment of a pad part anda magnet part of a mask chuck according to the invention; and

FIGS. 13A and 13B are views illustrating a state in which a mask chuckincluding a pad part and a magnet part which are illustrated in FIGS.12A and 12B stretches a cell mask.

DETAILED DESCRIPTION

In this specification, it will be understood that when an element (or aregion, a layer, portion, etc.) is referred to as being “on”, “connectedto” or “coupled to” another element or layer, it may be directly on,connected or coupled to the other element, or a third interveningelement may be therebetween.

Like reference symbols refer to like elements. Also, in the drawingfigures, the thicknesses, the ratios and the dimensions of elements areexaggerated for effective illustration of technological contents.

The term “and/or” includes all of one or more combinations that may bedefined by associated items.

Although the terms such as “first” and “second” may be used herein todescribe various elements, these elements should not be limited by theseterms. The terms are only used to distinguish one element from otherelements. For example, without departing from the scope of the presentinvention, a first component may be referred to as a second component,and similarly, the second component may also be referred to as the firstcomponent. Singular forms may include plural forms unless clearlydefined otherwise in context.

In addition, terms such as “under”, “below”, “on”, and “above” may beused to describe the relationship between elements illustrated in thedrawing figures. The terms have relative concepts, and are describedwith respect to directions illustrated in the drawing figures.

Unless defined otherwise, all terms (including technical terms andscientific terms) used in this specification have the same meaning asthat generally understood by those skilled in the art to which theinvention belongs. It will be further understood that terms, such asthose defined in commonly used dictionaries, should be interpreted ashaving a meaning that is consistent with their meaning in the context ofthe relevant art and will not be interpreted in an idealized or overlyformal sense unless so defined herein.

It should be further understood that the terms “include” or “have”, whenused in this specification, specify the presence of stated features,numbers, steps, operations, elements, components or combinationsthereof, but do not preclude the presence or addition of one or moreother features, numbers, steps, operations, elements, components, and/orcombinations thereof.

Hereinafter, embodiments will be described in detail with reference tothe accompanying drawings.

FIG. 1 is a view illustrating an embodiment of a mask.

Referring to FIG. 1, a mask MK may be used for a process formanufacturing a display device. Specifically, the mask MK may be usedfor a process for depositing an organic light-emitting element layer ona deposition substrate of a display device.

The mask MK may have a quadrangular (e.g., rectangular) parallelepipedshape. In an embodiment, the mask MK may have two sides extending in afirst direction DR1 and two sides extending in a second direction DR2,for example. The second direction DR2 indicates a direction crossing thefirst direction DR1.

The mask MK may be a thin plate having a small thickness in a thirddirection DR3. The third direction DR3 indicates a directionsubstantially perpendicularly crossing the plane defined by the firstdirection DR1 and the second direction DR2.

In a plan view, the mask MK may have a quadrangular (e.g., rectangular)shape. In this specification, the wording “in a plan view” means a stateof viewing an element from the top.

The mask MK may include a mask frame MF and a plurality of cell masksCMK. In an embodiment, the mask frame MF and the cell masks CMK mayinclude a metallic material such as stainless steel (“SUS”), an invaralloy, nickel (Ni), or cobalt (Co), for example. However, the materialsfor the mask frame MF and the cell masks CMK are not limited thereto.

The mask frame MF may have a quadrangular (e.g., rectangular) shapehaving two sides extending in the first direction DR1 and two sidesextending in the second direction DR2.

A plurality of cell openings COP may be defined in the mask frame MF.The cell openings COP may be arranged in the first direction DR1 and thesecond direction DR2.

In a plan view, the cell openings COP may each have a quadrangular(e.g., rectangular) shape. With respect to the third direction DR3, thecell openings COP may be defined as passing through the mask frame MF.

FIG. 1 illustrates four cell openings COP, but the invention is notlimited thereto, and the number of the cell openings COP may actually bemore than four. In addition, the shape of each of the cell openings COPmay be deformed according to the shape of the cell mask CMK.

Edge parts LP may each be defined as a portion of the mask frame MFsurrounding each of the cell openings COP. In a plan view, the edgeparts LP may each have a rectangular annular shape.

The cell masks CMK may each overlap the corresponding cell opening COPin a plan view. In an embodiment, in a plan view, the cell masks CMK mayeach have a rectangular shape, for example.

A plurality of deposition holes H may be defined in each of the cellmasks CMK. The deposition holes H may be defined as passing through thecell masks CMK in the third direction DR3. The width of each depositionhole H along the first direction DR1 or the second direction DR2 ischangeable. In an embodiment, with respect to the third direction DR3,the width of an upper portion of each deposition hole H may be greaterthan the width of a lower portion of each deposition hole H, forexample. However, the shapes of the deposition holes H are not limitedthereto.

The cell masks CMK may be disposed on the mask frame MF. In a plan view,the edge part of each cell mask CMK may overlap the edge part LP of themask frame MF.

The cell masks CMK may be fixed to the mask frame MF. In an embodiment,the cell masks CMK may be fixed to the mask frame MF by an intense light(e.g., laser beam), for example. This will be described in detail later.

FIG. 2 is a perspective view illustrating an embodiment of a mask chuckaccording to the invention. FIG. 3 is a perspective view verticallyinverting and illustrating the mask chuck illustrated in FIG. 2. FIG. 3is a view for describing a lower structure of the mask chuck MCillustrated in FIG. 2. Substantially, FIG. 3 illustrates the shape ofthe mask chuck MC “when viewed from under a pad part PD”.

Referring to FIGS. 2 and 3, the mask chuck MC may be used to manufacturethe mask MK illustrated in FIG. 1. The mask chuck MC may stretch thecell mask CMK illustrated in FIG. 1 and dispose the stretched cell maskCMK to the mask frame MF.

In an embodiment of the invention, the mask chuck MC may include a baseplate BP, a head part HE disposed under the base plate BP, a pad part PDdisposed under the head part HE, and a transfer part TP disposed on thebase plate BP.

The base plate BP may have a quadrangular (e.g., rectangular) shape in aplan view. The base plate BP may include an upper surface BP-U and alower surface BP-B. The upper surface BP-U and the lower surface BP-B ofthe base plate BP may each be parallel to the plane defined by the firstdirection DR1 and the second direction DR2.

The base plate BP may include a central region CA and an edge region OAdisposed around the central region CA. The central region CA may have aquadrangular (e.g., rectangular) shape in a plan view.

The edge region OA may surround the central region CA. Specifically, theedge region OA may include a first edge region OA1, a second edge regionOA2, a third edge region OA3, and a fourth edge region OA4.

The first edge region OA1 and the second edge region OA2 may extend inthe first direction DR1. The second edge region OA2 may be spaced apartfrom the first edge region OA1 in the second direction DR2. The centralregion CA may be disposed between the first edge region OA1 and thesecond edge region OA2.

A third edge region OA3 and a fourth edge region OA4 may extend in thesecond direction DR2. The fourth edge region OA4 may be spaced apartfrom the third edge region OA3 in the first direction DR1. The centralregion CA may be disposed between the third edge region OA3 and thefourth edge region OA4.

In an embodiment of the invention, an upper surface of the head part HEmay be disposed on the lower surface BP-B of the base plate BP. The headpart HE may overlap the edge region OA. Specifically, the head part HEmay include a first head part HE1, a second head part HE2, a third headpart HE3, and a fourth head part HE4.

The first to fourth head parts HE1 to HE4 may be disposed on the lowersurface BP-B of the base plate BP. The first to fourth head parts HE1 toHE4 may be separated from each other.

The first head part HE1 may overlap the first edge region OA1. Thesecond head part HE2 may overlap the second edge region OA2. The firsthead part HE1 and the second head part HE2 may each extend in the firstdirection DR1. In an embodiment, the first head part HE1 and the secondhead part HE2 may each have a quadrangular (e.g., rectangular)parallelepiped shape lengthily extending in the first direction DR1, forexample.

The third head part HE3 may overlap the third edge region OA3. Thefourth head part HE4 may overlap the fourth edge region OA4. The thirdhead part HE3 and the fourth head part HE4 may each extend in the seconddirection DR2. In an embodiment, the third head part HE1 and the fourthhead part HE2 may have a quadrangular (e.g., rectangular) parallelepipedshape lengthily extending in the second direction DR2, for example.

In an embodiment of the invention, the head part HE may move so as to beclose to the central region CA or away from the central region CA in theedge region OA. In an embodiment, a rail part may be disposed betweenthe head part HE and the base plate BP, for example.

Specifically, a first rail part RP1 may be disposed on the lower surfaceBP-B overlapping the first edge region OA1. The first rail part RP1 mayextend in the second direction DR2. A fourth rail part RP4 may bedisposed on the lower surface BP-B overlapping the fourth edge regionOA4 and extend in the first direction DR1.

Although not shown due to an observation position of FIG. 3, a secondrail part may be disposed on the lower surface BP-B overlapping thesecond edge region OA2. The second rail part may extend in the seconddirection DR2. A third rail part may be disposed on the lower surfaceBP-B overlapping the third edge region OA3 and extend in the firstdirection DR1.

The first to fourth head parts HE1 to HE4 may each move so as to becloser to the central region CA on the corresponding rail part or to befarther from the central region CA. Specifically, the first head partHE1 and the second head part HE2 may move in the second direction DR2and the third head part HE3 and the fourth head part HE4 may move in thefirst direction DR1. The first to fourth head parts HE1 to HE4 may movesimultaneously or independently.

However, the movement method of the head part HE is not limited to thosedescribed above. In an embodiment, a method may be used in which arecess is defined in the lower surface BP-B of the base plate BP, andthe head part HE moves while a portion of the head part HE is insertedin the recess, for example.

FIG. 4 is a perspective view illustrating an embodiment of a pad partdisposed on a lower surface of a fourth head part among the pad partsillustrated in FIG. 3. For convenience of description, in FIG. 4, thepad part PD illustrated in FIG. 2 is illustrated in a verticallyinverted shape.

Referring to FIGS. 3 and 4, the pad part PD may be disposed on the headpart HE. Specifically, the pad part PD may be disposed on the lowersurface of the head part HE.

A plurality of pad parts PD may be provided. In an embodiment, the padpart PD may be disposed under each of the first to fourth head parts HE1and HE4, for example.

The pad part PD may extend in the extension direction of thecorresponding head parts HE1 to HE4. In an embodiment, the pad part PDdisposed under the lower surface of each of the first head part HE1 andthe second head part HE2 may extend in the first direction DR1, forexample. The pad part PD disposed on the lower surface of each of thethird head part HE3 and the fourth head part HE4 may each extend in thesecond direction DR2.

The pad part PD may include a first pad PD1 and a second pad PD2disposed adjacent to the first pad PD1. The first pad PD1 and the secondpad PD2 may be disposed in parallel in the lengthwise direction thereof.In an embodiment, referring to FIGS. 3 and 4, the first pad PD1 and thesecond pad PD2 which are disposed on the lower surface of the fourthhead part HE4 may each extend in the second direction DR2 and bedisposed parallel to the second direction DR2, for example.

In an embodiment of the invention, the first pad PD1 may be disposedmore adjacent to the central region CA than the second pad PD2 is to thecentral region CA. In other words, the first pad PD1 may be disposed onthe inner side on the lower surface of the head part HE, and the secondpad PD2 may be disposed on the outer side on the lower surface of thehead part HE.

In an embodiment of the invention, the first pad PD1 may have a porousstructure. In an embodiment, a plurality of first holes H1 may bedefined in the first pad PD1, for example. The first holes H1 may beirregularly defined in the surface of the first pad PD1. The first holesH1 may be defined on all of the first lower surface BF1, side surfaces,and the first upper surface UF1 of the first pad PD1.

The first lower surface BF1 and the first upper surface UF1 of the firstpad PD1 may communicate with each other by the first holes H1. The firstupper surface UF1 refers to a surface facing the lower surface of thehead part (for example, the fourth head part HE4 illustrated in FIG. 3)corresponding to the first pad PD1. The air flowing into the first lowersurface BF1 of the first pad PD1 may flow out of the first upper surfaceUF1.

In an embodiment of the incentive concept, a second hole H2 may bedefined in the second pad PD2. When viewed from under the pad part PD,the area of the second hole H2 may be greater than the area of each ofthe first holes H1. In an embodiment, the second hole H2 may be definedas a line shape, for example.

In an embodiment, as illustrated in FIG. 4, in the case of the secondpad PD2 disposed on the fourth pad head part HE4, the second hole H2 mayextend lengthily in the second direction DR2, for example.

The second hole H2 may pass through the second pad PD2 in the thicknessdirection (for example, the third direction DR3). The upper portion andthe lower portion of the second pad PD2 may communicate with each otherby the second hole H2. The upper portion refers to a portion adjacent tothe head part HE in the second pad PD2, and the lower portion refers toa portion opposite to the upper portion in the second pad PD2.

In an embodiment of the invention, the head part HE may include apneumatic control part (not shown). The pneumatic control part may bedisposed inside the head part HE. The pneumatic control part may beconnected to the first upper surface UF1 of the first pad PD1 and theupper portion of the second pad PD2. The pneumatic control part maysuction air. In an embodiment, the pneumatic control part may includeone or more flow paths and a blower, for example.

The pneumatic control part may form a negative pressure on the lowersurface BF1 of the first pad PD1 and in a lower portion of the secondpad PD2. Accordingly, the air in the surrounding of the lower surfaceBF1 of the first pad PD1 and the lower portion of the second pad PD2 maybe suctioned and flow into the head part HE through the first pad PD1and the second pad PD2.

In an embodiment of the invention, the first lower surface BF1 of thefirst pad PD1 and the second lower surface BF2 of the second pad PD2 maybe disposed coplanar with each other. The first lower surface BF1 of thefirst pad PD1 and the second lower surface BF2 of the second pad PD2 maycontact a target object.

The area of the second hole H2 may be greater than the sum of the firstholes H1 defined in the first lower surface BF1. Accordingly, when thepneumatic control part operates, the suction force generated in thelower portion of the second pad PD2 may be greater than the suctionforce generated in the first lower surface BF1 of the first pad PD1. Inother words, the force acting between the second pad PD2 and the targetobject may be greater than the force acting between the first pad PD1and the target object.

Referring back to FIG. 2, the mask chuck MC may further include atransfer part TP. The transfer part TP may be connected to the uppersurface BP-U of the base plate BP and may move the base plate BP. Thetransfer part TP may move the base plate BP in the first to thirddirections DR1 to DR3.

FIG. 5A is a view illustrating a state before the cell mask illustratedin FIG. 1 is stretched. FIG. 5B is a view illustrating a state in whichthe mask chuck illustrated in FIG. 2 picks the cell mask illustrated inFIG. 5A.

Referring to FIG. 5A, the cell mask CMK may be in a state before thecell mask CMK illustrated in FIG. 1 is stretched. A plurality ofdeposition holes H′ may be defined in the cell mask CMK′. In a planview, the area of the cell mask CMK′ may be smaller than the area of thecell mask CMK illustrated in FIG. 1. In a plan view, the area of thedeposition hole H′ may be smaller than the area of the deposition hole Hillustrated in FIG. 1.

Wing parts may be disposed on the periphery of the cell mask CMK′. In anembodiment, the wing parts may each extend from the periphery of thecell mask CMK′, for example. Specifically, a first wing part FP1 and asecond wing part FP2 may extend from the cell mask CMK′ in the seconddirection DR2. A third wing part FP3 and a fourth wing part FP4 may eachextend from the cell mask CMK′ in the first direction DR1.

The first to fourth wing parts FP1 to FP4 may be unitary with the cellmask CMK′. In an embodiment, the first to fourth wing parts FP1 to FP4may include a metallic material, for example. The first to fourth wingparts FP1 to FP4 may be removed from the process to be described later.

Referring to FIGS. 5A and 5B, the mask chuck MC may pick the cell maskCMK′. In an embodiment, the transfer part TP may dispose the base plateBP on the cell mask CMK′, for example. The transfer part TP may lowerthe base plate BP and bring the pad part PD into contact with the cellmask CMK′.

In a plan view, the first head part HE1 of the mask chuck MC may overlapthe first wing part FP1. The pad part PD disposed on the lower surfaceof the first head part HE1 may contact the upper surface of the firstwing part FP1. Specifically, the first pad PD1 may contact an innerportion adjacent to the cell mask CMK′ on the upper surface of the firstwing part FP1, and the second pad PD2 may contact the outer portion ofthe upper surface of the first wing part FP1.

The second head part HE2 of the mask chuck MC may overlap the secondwing part FP2. The pad part PD disposed on the lower surface of thesecond head part HE2 may contact the upper surface of the second wingpart FP2. The third head part HE3 may overlap the third wing part FP3,and the pad part PD disposed on the lower surface of the third head partHE3 may contact the upper surface of the third wing part FP3. Althoughnot shown, the pad part PD disposed on the lower surface of the fourthhead part HE4 may contact the upper surface of the fourth wing part FP4.

The cell masks CMK′ may be fixed onto the mask chuck MC. In anembodiment, when the pneumatic control part of the head part HEoperates, the wing parts FP1 to FP4 may be suctioned and attached to thepad parts PD, for example. As described above, the suction force betweenthe second pad PD2 and the wing parts FP1 to FP4 may be greater than thesuction force between the first pad PD1 and the wing parts FP1 to FP4.

FIG. 6A is a view illustrating a state in which the mask chuckillustrated in FIG. 5B stretches a cell mask. FIG. 6B is a viewillustrating a state in which the cell mask illustrated in FIG. 5A isstretched.

Referring to FIG. 6A, the mask chuck MC may stretch the cell mask CMK′.Specifically, in a state in which the wing parts FP1 to FP4 are fixed tothe pad part PD, the mask chuck MC may move the head part HE in adirection from the inside toward the outside.

Specifically, with respect to FIG. 6A, the first head part HE1 may movein the leftward direction and the second head part HE2 may move in therightward direction. Accordingly, the cell mask CMK′ may be stretched inthe second direction DR2. Furthermore, the third head part HE3 may movein a direction piercing out of FIG. 6A. The fourth head part HE4 maymove in a direction piercing into FIG. 6A. Accordingly, the cell maskCMK′ may be stretched in the first direction DR2. The directions inwhich the first to fourth head parts HE1 to HE4 are illustrated indetail in FIG. 3.

Referring to FIG. 6B, the cell mask CMK′ may mean a state in which thecell mask CMK′ illustrated in FIG. 5A is stretched. Specifically, in aplan view, the area of a stretched cell mask CMK′ may be greater thanthe area of the cell mask CMK′ of FIG. 5A. The area of the stretchedcell mask CMK′ excluding the wing parts FP1 to FP4 may be equal to thecell mask CMK illustrated in FIG. 1. The area of the deposition hole Hmay be equal to the area of the deposition hole H illustrated in FIG. 1.

FIG. 7 is a view illustrating a state in which the mask chuckillustrated in FIG. 6A disposes a cell mask on a mask frame. FIG. 8 is aview illustrating a state in which the cell mask illustrated in FIG. 7is fixed to a mask frame.

Referring to FIG. 7, a mask chuck MC may dispose a stretched cell maskCMK on a mask frame MF disposed on a stage ST. The disposition of thecell mask CMK may be performed by a transfer part TP.

The edge part of the cell mask CMK and a wing part FP may contact theupper surface of the mask frame MF.

Referring to FIG. 8, an intense-light emitting apparatus (e.g., laserapparatus) LD1 may irradiate a first laser beam LZ1 on a contact surfacebetween the edge part of the cell mask CMK and the upper surface of themask frame MF making contact with the edge part. In an embodiment, thefirst laser apparatus LD1 may be disposed under the mask frame MF andemit the first laser beam LZ1 in an upward direction, for example.

A portion of the cell mask CMK adjacent to the contact surface or aportion of the mask frame MF may be melted by the first laser beam LZ1.The cell mask CMK may be fixed to the mask frame MF while portionsmelted by the first laser bean LZ1 are cooled.

A second laser apparatus LD2 may remove the wing parts FP from the cellmask CMK. In an embodiment, the second laser apparatus LD2 may bedisposed above the cell mask CMK, and emit a second laser beam LZ2 in adownward direction, for example. The second laser beam LZ2 may beemitted to a boundary between the cell mask CMK and the wing parts FP.The second laser beam LZ2 may cut a boundary portion between the cellmask CMK and the wing parts FP.

Consequently, the cell mask CMK may be fixed to the mask frame MF by theabove-described processes as illustrated in FIG. 1.

The mask chuck MC in an embodiment of the invention may perform not onlythe function for disposing the cell mask CMK on the mask frame MF, butalso the stretching process. Accordingly, the mask manufacturing processmay be simplified and the yield thereof may be improved.

In an embodiment of the invention, when the mask chuck MC contacts thewing part FP of the cell mask CMK and stretches the cell mask CMK, thefirst pad PD1 having relatively small suction force maybe disposedadjacent to the cell mask CMK and the second pad PD2 having relativelygreat suction force may be separated from the cell mask CMK, andtherefore the deformation of the cell mask CMK may be minimized.

In an embodiment of the invention, a surface treatment process may beperformed on the upper surfaces of the wing parts FP. The surfacetreatment process may improve the suction force between the wing part FPand the pad part PD by decreasing the surface roughness of the uppersurfaces of the wing parts FP. Accordingly, when the cell mask CMK isstretched, a slip phenomenon occurring between the wing part FP and thepad part PD may be improved.

Hereinafter, the mask chucks according to other embodiments of theinvention will be described. The mask chucks below in embodiments mayhave the same configuration as the mask chuck MC according to theabove-described embodiments excluding the configurations (for example,pad driving part and magnet part) disposed on the pad part and insidethe pad part. Hereinafter, descriptions on the same configuration willbe omitted and the configuration different from the above-describedembodiments will be described in detail.

FIG. 9 is a view illustrating an embodiment of a pad part of a maskchuck according to the invention. For convenience of description, inFIG. 9, a pad part PD-1 and a head part HE is vertically inverted andillustrated.

Referring to FIG. 9, the pad part PD-1 may be disposed on a lowersurface of the head part HE and extend in the lengthwise direction ofthe head part HE. The pad part PD-1 may include a first pad PD1-1 and acoating layer CT. The first pad PD 1-1 may be disposed on the lowersurface of the head part HE. The first pad PD1-1 may have substantiallythe same structure as the first pad PD1 illustrated in FIG. 4.

In an embodiment, a plurality of first holes H1-1 may be defined in thefirst pad PD1-1, for example. The first holes H1-1 may be irregularlyarranged in the surface of the first pad PD1-1.

The coating layer CT may be disposed on the lower surface of the firstpad PD1-1. The coating layer CT may substantially be provided by coatingthe lower surface of the first pad PD1-1 with a predetermined material.The coating layer CT may not overlap the first holes H1-1.

The lower surface CT-B of the coating layer CT may have a greaterfriction coefficient than that of the lower surface of the first padPD1-1.

In an embodiment of the invention, the coating layer CT including amaterial having a large friction coefficient than that of the first padPD1-1 is further disposed on the lower surface of the pad part PD1, andthus, when the mask chuck performs a stretching process, the problem ofcausing a slip phenomenon between the cell mask CMK and the pad partPD-1 may be solved.

FIGS. 10A and 10B are views illustrating a pad part of a mask chuckaccording to the invention. For convenience of description, in FIGS. 10Aand 10B, a pad part PD-2 and a head part HE-2 are vertically invertedand illustrated.

Referring to FIG. 10A, a pad part PD-2 may include a first pad PD2-1 anda second pad PD2-2. The first pad PD2-1 may extend in the lengthwisedirection (for example, the second direction DR2) of the head part HE-2.The first pad PD2-1 may be disposed on a central portion of the lowersurface of the head part HE-2. When viewed from under the pad part PD-2,the first pad PD2-1 may have a quadrangular (e.g., rectangular) shapeextending lengthily in the second direction DR2.

The first pad PD2-1 may have substantially the same structure as thefirst pad PD1 illustrated in FIG. 4. In an embodiment, a plurality offirst holes H1-2 may be defined in the surface of the first pad PD2-1,for example. The first pad PD 1-2 may be connected to a pneumaticcontrol part disposed inside the head part HE-2.

The second pad PD2-2 may surround the first pad PD2-1. In an embodiment,from under the pad part PD-2, the second pad PD2-2 may be disposedextending along the periphery of the first pad PD2-1, for example. In anembodiment, the second pad PD2-2 may have a quadrangular (e.g.,rectangular) annular shape, for example.

A first lower surface BF1-2 of the first pad PD2-1 may have a firstfriction coefficient. A second lower surface BF2-2 of the second padPD2-2 may have a second friction coefficient. In this embodiment, thesecond friction coefficient may be greater than that of the firstfriction coefficient.

Referring to FIG. 10B, the position of the first pad PD2-1 may vary. Inan embodiment, the first pad PD2-1 may be connected to a pad drivingpart. The pad driving part may be disposed inside the head part HE-2,for example. The pad derive part may be connected to a first uppersurface of the first pad PD2-1. The first upper surface may be a surfaceopposite the first lower surface BF1-2 in the third direction DR3. Thepad driving part may move the first pad PD2-1 in a direction (forexample, the third direction DR3) perpendicular to the first lowersurface BF1-2.

FIGS. 11A and 11B are views illustrating a state in which a mask chuckincluding the pad part and the head part which are illustrated in FIGS.10A and 10B stretches a cell mask.

Referring to FIG. 11A, a first lower surface BF1-2 of a first pad PD2-1protrudes further downward (for example, in the third direction DR3)than a second lower surface BF2-2 of a second pad PD2-2. The first lowersurface BF1-2 of the first pad PD2-1 may first contact a wing part FP.The wing part FP may be any one among the wing parts FP1 to FP4illustrated in FIG. 5A.

While the first pad PD2-1 is in contact with the wing part FP, thepneumatic control part may fix the wing part FP to the first pad PD2-1.

Referring to FIG. 11B, the second lower surface BF2-2 of the second padPD2-2 may contact the wing part FP. The second pad PD2-2 may contact thewing part FP as the pad driving part moves the position of the first padPD2-1 in the third direction DR3. While the first pad PD2-1 and thesecond pad PD2-2 are in contact with the wing part FP, the head partHE-2 may move outward (rightward direction with respect to FIG. 11B).Accordingly, the cell mask CMK′ may be stretched.

In an embodiment of the invention, while the wing part FP is fixed tothe first pad PD2-1 by vacuum suction force, the second pad PD2-2 havinga greater friction coefficient than that of the first pad PD2-1 maycontact the wing part FP. Accordingly, when extending the cell maskCMK′, a slip phenomenon between the wing part FP and the pad part PD-2is improved and a stretching process with high completeness may beperformed.

FIGS. 12A and 12B are views illustrating an embodiment of a pad part anda magnet part of a mask chuck according to the invention. Forconvenience of description, in FIGS. 12A and 12B, a pad part PD-3 and ahead part HE-3 are vertically inverted and illustrated.

Referring to FIGS. 12A and 12B, a plurality of first holes H1-3 may bedefined in the pad part PD-3. A first upper surface and a first lowersurface of the pad part PD-3 may communicate with each other via firstholes H1-3. The first upper surface of the pad part PD-3 may beconnected to a pneumatic control part.

According to this embodiment, the mask chuck may further include amagnet part MP. The magnet part MP may be disposed between the pad partPD-3 and a base plate BP (refer to FIG. 3). In an embodiment, the magnetpart MP may be disposed inside the head part HE-3, for example. Themagnet part MP may move inside the head part HE-3. In an embodiment, themagnet part MP may move in the third direction DR3 and move so as to beclose to the pad part PD-3 or away from the pad part PD-3, for example.

In this embodiment, the magnet part MP may include a permanent magnet.However, the invention is not limited thereto, and the magnet part MPmay also include an electromagnet.

FIGS. 13A and 13B are views illustrating a state, in which a mask chuckincluding the pad part and the magnet part which are illustrated inFIGS. 12A and 12B, stretches a cell mask.

Referring to FIG. 13A, a pad part PD-3 may contact a wing part FP. Amagnet part MP may be disposed at a position spaced apart from the padpart PD-3 in the third direction DR3. A pneumatic control part may fix awing part FP to the pad part PD-3 through vacuum suction force. The wingpart FP may be one among the wing parts FP1 to FP4 illustrated in FIG.5A.

Referring to FIG. 13B, the magnet part MP may move so as to be close tothe pad part PD-3. Ad described above, the wing parts FP may include ametallic material. Accordingly, attractive force may act between themagnet part MP and the wing part FP. Consequently, the attractive forcebetween the pad part PD-3 and the wing part FP may increase.

When the magnet MP is disposed adjacent to the pad part PD-3, the headpart HE-3 may move in an outward direction (that is, rightward directionwith respect to FIG. 13B). Accordingly, the cell mask CMK′ may bestretched.

A mask chuck MC in an embodiment of the invention further includes themagnet part MP which is disposed inside the head part HE-3 so as to beclose to or away from the pad part PD-3, and thus may easily control thecoupling force between the pad part PD-3 and the wing part FP. In anembodiment, when stretching the cell mask CMK′, the magnet part MP isdisposed adjacent to the pad part PD-3 and may fix the wing part FP withstronger force, for example. Accordingly, a slip phenomenon between thewing part FP and the pad part PD-3 may be mitigated.

In an embodiment of the invention, a mask chuck may pick a cell maskthrough a pad part and a transfer part and dispose the cell mask on amask frame, and also stretch a cell mask through a head part connectedto the pad part and moving in an edge region.

So far, the invention has been described in connection with preferredembodiments thereof. However, those of ordinary skill in the art willrecognize that various modifications and variations are possible withoutdeparting from the spirit and scope set forth in the following claims.In addition, embodiments disclosed herein are not intended to limit thespirit and scope of the invention. Rather, the appended claims and alltechnical idea within the range equivalent thereto should be understoodto be included in the spirit and scope of the invention.

What is claimed is:
 1. A mask chuck comprising: a base plate including acentral region and an edge region surrounding the central region, theedge region comprising: a first edge region extending in a firstdirection; a second edge region extending in the first direction andspaced apart from the first edge region in a second direction crossingthe first direction; a third edge region extending in the seconddirection; and a fourth edge region extending in the second directionand spaced apart from the third edge region in the first direction, ahead part including a first surface connected to the edge region of thebase plate and configured to move on the edge region so as to be closeto the central region or away from the central region, the head partcomprising: a first head part disposed in the first edge region andextending in the first direction; a second head part disposed in thesecond edge region and extending in the first direction; a third headpart disposed in the third edge region and extending in the seconddirection; and a fourth head part disposed in the fourth edge region andextending in the second direction, and a pad part disposed on a secondsurface of the head part which is opposite to the first surface of thehead part.
 2. The mask chuck of claim 1, wherein the pad part comprises:a first pad disposed on the second surface of the head part and in whicha plurality of first holes defined; and a second pad disposed adjacentto the first pad and in which a second hole defined, wherein, in a planview, the second hole has a greater area than an area of a first hole ofthe plurality of first holes.
 3. The mask chuck of claim 2, wherein thefirst pad and the second pad extend in parallel in one direction.
 4. Themask chuck of claim 3, wherein in the plan view, the first pad isdisposed more adjacent to the central region than the second pad is tothe central region.
 5. The mask chuck of claim 2, wherein a firstsurface of the first pad opposite to the base plate and a first surfaceof the second pad opposite to the base plate are disposed coplanar witheach other.
 6. The mask chuck of claim 2, wherein: a first surface ofthe first pad facing the base plate and a second surface of the firstpad opposite to the first surface of the first pad communicate with eachother via the plurality of first holes; and a first portion of thesecond pad facing the base plate and a second portion of the second padwhich is opposite to the first portion of the second pad communicatewith each other via the second hole.
 7. The mask chuck of claim 6,wherein the head part comprises a pneumatic control part connected tothe first surface of the first pad and the first portion of the secondpad, the pneumatic control part being configured to suction air aroundthe second surface of the first pad and the second portion of the secondpad.
 8. The mask chuck of claim 2, wherein the plurality of first holesis irregularly defined in a surface of the first pad.
 9. The mask chuckof claim 2, wherein the second hole extends in a lengthwise direction ofthe second pad, and passes through the second pad in a thicknessdirection of the second pad.
 10. The mask chuck of claim 1, wherein thefirst to fourth head parts are separated from each other.
 11. The maskchuck of claim 1, wherein: each of the first head part and the secondhead part move in the second direction so as to be close to the centralregion or away from the central region; and the third head part and thefourth head part move in the first direction so as to be close thecentral region to or away from the central region.
 12. The mask chuck ofclaim 1, wherein the pad part comprises: a first pad including a firstsurface opposite to the base plate and having a first frictioncoefficient; and a second pad disposed adjacent to the first pad andincluding a first surface opposite to the base plate and having a secondfriction coefficient, the second friction coefficient being greater thanthe first friction coefficient.
 13. The mask chuck of claim 12, whereinin a plan view, the second pad surrounds the first pad.
 14. The maskchuck of claim 13, wherein the first pad is configured to move in adirection perpendicular to a second surface of the first pad opposite tothe first surface of the first pad.
 15. The mask chuck of claim 1,comprising a magnet part disposed between the base plate and the padpart and configured to move so as to be close to the pad part or awayfrom the pad part, the magnet part being disposed inside the head part.16. The mask chuck of claim 15, wherein the magnet part comprises atleast one permanent magnet.